On reflective subcategories of varieties

• DOI: 10.1016/j.jalgebra.2003.09.039
• Publication Date: 2003-12-17T05:43:35Z
• Authors: Jiřı́ Adámek; Lurdes Sousa
• Keywords: 0209 industrial biotechnology; Algebra and Number Theory; 02 engineering and technology

AbstractFull reflective subcategories of varieties are characterized as the cocomplete categories with a regular generator, or as classes of algebras presented by “preequations.” As a byproduct, a solution is presented to the problem of describing ω-orthogonality classes of locally finitely presentable categories in terms of closure properties.